Porphyrins and Metalloporphyrins : An Overview

Porphyrin macrocycles have been the subject of intense study in the last century and the last two decades because they are widely distributed in nature. As such, they serve as the prosthetic groups in a wide variety of primary metabolites, such as hemoglobin, myoglobin, cytochromes, catalases, peroxidases, chlorophylls, and bacteriochlorophylls. These species present a tetrapyrrolic ring known as porphyrin. The resulting aromaticity gives rise to the semiconducting properties that make these compounds of interest for a broad range of applications, including artificial photosynthesis, catalysis, molecular electronics, sensors, non-linear optics, and solar cells. Among the many applications of porphyrins and metalloporphyrins, the focus will be on the photodynamic therapy (PDT) of cancer.